The curl-up tests the strength and endurance of the abdominal muscles, while the arm hang tests the strength and endurance of the arm muscles. Since different muscle groups are developed and tested in different ways, tests for different groups cannot be used interchangeably because the results do not pertain to the same group of muscles.
Stephan is doing a school report on cities with high amounts of air pollution. Which of the following diseases should he focus on in his description of possible effects of air pollution?